AASHTO A Synthesis of Safety Implications of Oversize Overweight Commercial Vehicles First Edition The objective of this report is to identify known relationships between commercial vehicle safety and crash causation factors and to prepare a synthesis of safety implications of oversize overweight (OS/OW) commercial vehicles.

This AASHTO A Synthesis of Safety Implications of Oversize Overweight Commercial Vehicles can be used to support commercial vehicle enforcement and permitting practices and justify expenditures and investments on size and weight enforcement to enhance safety. In producing this report, insight was gained into the impacts of truck size and weight (TSW) regulations through three case studies.

AASHTO A Synthesis of Safety Implications of Oversize Overweight Commercial Vehicles The state of practice in estimating large truck crash rates is complicated because of the many configurations and the wide range of possible weights for any particular configuration. This report highlights four primary findings regarding the contributions of OS/OW to commercial vehicle crashes found by its researchers.

Section 5. Heavy Truck Crashes in General
Early Large Truck Safety Research
More Recent Large Truck Safety Research
Enforcement : Roadside Inspections, Weigh Stations
Overview of Fatal Large Truck Crashes
Section Summary

Section 6. Data Associated with OS/OW Heavy Vehicles
Two Meanings for OS/OW Vehicles
Comprehensive Data Is Necessary
Data Sets with Promise
Data for Which OS/OW was Established or Probable
Data for LCVs and Other Large, Heavy Commercial Vehicles